FOSTER CITY -- It was to be one of life's signature moments of happiness, something that always would be remembered, as a stylish evening meant to be richly shared with good friends. Nine women had happily tumbled into a stretch limousine for a girl's night out to celebrate the recent wedding of one.

They were heading for a bridal shower in Foster City Saturday night when, over the span of the San Mateo Bridge just after 10 p.m., sheer joy turned into unimaginable horror.

For reasons that are still unexplained, the interior of the white 1999 Lincoln Town Car suddenly became engulfed in flames, killing five of the women -- including the bride -- who were unable to escape the raging inferno. A veteran coroner was quoted as saying the incident was one of the worst he had ever witnessed. The deceased were so badly burned that positive identifications will require dental records. And grieving friends and family are trying to make sense of the tragedy.

"She is everything," said the distraught brother-in-law Joseph Bersamin, of Neriza Fojas, the woman celebrating her marriage, who perished in the flames. Speaking by phone from Honolulu, Bersamin added, "she is so nice to everyone."

Fojas, 31, a registered nurse from Fresno, was actually planning to repeat her marriage vows in the Philippines next month. Although Fojas' identity was learned Sunday as the heart-wrenching story became national news, the San Mateo County Coroner's Office will not be releasing the names of the victims until Monday at the earliest.

Driver unhurt

The four surviving women, who managed to somehow escape the burning limousine, were transported to area hospitals to be treated for burns and smoke inhalation, according to the California Highway Patrol. Jasmine Desguia, 34, of San Jose, and Amalia Loyola, 48, of San Leandro, were listed in critical condition at Santa Clara Valley Medical Center, said hospital spokeswoman Joy Alexiou.

Mary G. Guardiano, 42, of Alameda, and Nelia Arrellano, 36, of Oakland, were taken to Stanford University Medical Center, according to the CHP. But Stanford would not confirm if they were being treated at the hospital.

Driver Orville Brown, 46, of San Jose, emerged unhurt.

So much about the tragedy remained unknown Sunday as authorities attempted to piece together what exactly happened.

San Mateo County Coroner Robert Foucrault said the limousine picked up the women in Oakland and was taking them to the Crowne Plaza Foster City on Chess Drive as part of a bridal shower. The event was to honor Fojas, who is actually already married. She and her husband were intending to travel to the Philippines for a ceremony and reception for family on June 19.

At least some of the women knew each other through nursing jobs, said Angela Huang, a nursing supervisor at Crown Bay Nursing and Rehabilitation Center in Alameda.

Huang said she worked the same shift as Guardiano, who went by the name Grace. She said Loyola was also a former employee at the nursing home.

At about 10:05 p.m., the CHP responded to a call of a vehicle fire in a westbound lane of the decline portion of the bridge approaching the shore. While it wasn't clear what sparked the inferno, it wasn't the result of a traffic accident. It appears that smoke began to appear at the rear of the vehicle, and then was followed by flames, which spread quickly. The women alerted the driver, who managed to pull over the limousine. But CHP Officer Art Montiel said only four of the passengers managed to escape.

"Deeply saddened"

Photographs by a Bay Area News Group photographer captured the devastating aftermath when emergency workers extinguished the fire. The rear of the vehicle was reduced to an ashen, burned-out hulk.

Brown was allowed to go home early Sunday morning. Pam Kaur, a dispatcher for Limo Stop, which operates the vehicle, said Sunday that the company is assisting the CHP with the ongoing investigation -- something that authorities confirmed.

"We are very shocked," said Kaur, who added that she wasn't aware of any problems with the car. "We are cooperating with the police."

A callback phone request to company CEO Kultar Singh wasn't returned. But Limo Stop released a statement, according to NBC News, saying it was "deeply saddened" by the tragedy.

"Limo Stop, Inc. will do everything possible to investigate and assist authorities in determining the cause of this fire in order to bring forth answers and provide closure to (the) victims and their families," the statement added.

According to records from the California Public Utilities Commission, which regulates limousine companies, Limo Stop is licensed and insured. It was not immediately clear if the company had been cited for previous safety problems.

All westbound lanes of the highway were closed for several hours late Saturday evening and into the early Sunday hours as authorities investigated the scene.